other uses Mergefrom Condensation aerosol dynamics date June 2009 cleanup date October 2010 Image condensation ... of a cold bottle. Image Window in Ireland.jpg right thumb Condensation on a window during a rain shower. File Cloud over A340 wing.JPG thumb right Condensation forming over the wing of an aircraft in a low pressure zone Condensation is the change of the physical state of matter from gaseous phase into liquid phase, and is the reverse of evaporation . ref GoldBookRef title condensation ... colder entity either a center of condensation within the gas volume colder molecules of the species, cold grains of dust etc. or some contact surface. Condensation is initiated by the formation ... solvents is reversible as evaporation . ref GoldBookRef title condensation in atmospheric chemistry ... as Sublimation Physics sublimation . Condensation commonly occurs when a vapor is cooled and or compressed ... Condenser heat transfer condenser . Psychrometry measures the rates of condensation from and evaporation ... of its vapor condensationcondensation is the process of such phase conversion. Applications of condensationCondensation is a crucial component of distillation , an important laboratory and industrial chemistry application. Because condensation is a naturally occurring phenomenon, it can often be used ... of collecting water from condensation, such as Air well condenser air wells and fog fence s. Such systems ... made accessible by condensation. A few examples are the Australian Thorny Devil , Darkling beetle .... See also Air well condenser Kelvin equation Retrograde condensation Phase diagram Phase transition Condenser heat transfer Surface condenser Bose Einstein condensate DNA condensation Notes reflist References cite web url http www.ces.purdue.edu pork images jones condense.jpg title Condensation principles Picture External links http www.diydata.com problem condensation condensation.php Guide to condensation in buildings and how to overcome This table shouldn t be here. It s internal, not external ... more details
Wiktionary condensationCondensation or condensed may refer to Condensation , the change in matter of a substance to a denser phase DNA condensation , the process of compacting DNA molecules Condensation in aerosol dynamics , a phase transition from gas to liquid Condensation reaction , in chemistry, a chemical reaction between two molecules or moieties Condensation algorithm , in computer science, a computer vision algorithm Condensation graph theory , in mathematics, a directed acyclic graph formed by contracting the strongly connected components of another graph Condensed font, a typeface drawn narrower than normal width See also intitle condensation intitle condensed disambig fr Condensation homonymie sk Kondenz cia ... more details
Image AminoacidCondensation.svg right frame 600px The condensation of two amino acid s to form a peptide bond red with expulsion of water blue A condensation reaction is a chemical reaction in which two ... of a small molecule. ref name Gold GoldBookRef title Condensation Reaction file C01238 year 1994 ... lost are hydrogen chloride , methanol , or acetic acid . The word condensation suggests a process in which two or more things are brought together Latin con to form something dense , like in condensation from gaseous to liquid state of matter this does not imply, however, that condensation reaction products have greater density than reactants. When two separate molecules react, the condensation is termed intermolecular . A simple example is the condensation of two amino acid s to form the peptide ..., the reaction is termed intramolecular condensation, and in many cases leads to ring formation. An example is the Dieckmann condensation , in which the two ester groups of a single diester molecule ... Condensation Scheme.png centre thumbnail 300px Dieckmann condensation reaction Mechanism Many condensation reactions follow a nucleophilic acyl substitution or an aldol condensation reaction mechanism . Other condensations, such as the acyloin condensation are triggered by Radical chemistry radical or single electron transfer conditions. Condensation reactions in polymer chemistry In one type of polymerization reaction, a series of condensation steps take place whereby monomer s or monomer chains add to each other to form longer chains. This is termed condensation polymerization or step ..., or a copolymer ization of two co monomers A A and B B. Small molecules are usually liberated in these condensation ..., condensation polymers form more slowly than addition polymers, often requiring heat. They are generally ... important polymer s for example nylon , polyester and other condensation polymer s and various ... s. The reactions that form acid anhydride s from their constituent acids are typically condensation ... more details
Retrograde condensation occurs when gas in a tube is compressed beyond the point of condensation with the effect that the liquid evaporates again. This is the opposite of condensation the so called retrograde condensation. Description If the volume of two gases which are kept at constant temperature and pressure below critical conditions is gradually reduced, condensation will start. When a certain volume is reached, the amount of condensation will gradually increase upon further reduction in volume until the gases are liquefied. If the composition of the gases lies between their true and pseudo Critical point thermodynamics critical point s the condensation formed will disappear on continued reduction of volume. ref http www.knaw.nl waals pdf Com4 Kuenen2.pdf On retrogade condensation and the critical phenomena of mixtures of two substances ref ref http www.knaw.nl waals pdf Com8 Kuenen.pdf On the abnormal phenomena near the critical point ref The disappearance of condensation is called retrograde condensation. Because natural gas is not a pure product, when non associated gas is extracted from a field under supercritical pressure temperature conditions when the pressure in the reservoir decreases below dewpoint , it may partially condense upon Isothermal process isothermic depressurizing instead of expanding or vaporizing, an effect called retrograde condensation. Discovery Johannes Petrus Kuenen discovered retrograde condensation and published his findings in April 1892 with the title Metingen betreffende het oppervlak van Van der Waals voor mengsels van koolzuur en chloormethyl Measurements on the surface of Van der Waal s for mixtures of carbonic acid and methyl chloride . ref http de.scientificcommons.org 2421376 Metingen betreffende het oppervlak van Van der Waals voor mengsels van koolzuur en chloormethyl ref ref http www.knaw.nl waals pdf Com4 Kuenen.pdf Measurements on the surface of Van der Waals for mixtures of carbonic acid and methyl chloride ref References ... more details
Unreferenced date July 2008 Condensation polymers are any kind of polymer s formed through a condensation reaction , releasing small molecules as by products such as water or methanol, as opposed to addition polymer s which involve the reaction of unsaturated monomer s. Types of condensation polymers include polyamide s, polyacetal s and polyester s. Condensation polymerization, a form of step growth polymerization , is a process by which two molecules join together, resulting loss of small molecules which is often water. The type of end product resulting from a condensation polymerization is dependent on the number of functional end groups of the monomer which can react. Monomers with only one reactive group terminate a growing chain, and thus give end products with a lower molecular weight. Linear polymers are created using monomers with two reactive end groups and monomers with more than two end groups give three dimensional polymers which are crosslinked. Dehydration synthesis often involves joining monomers with an OH hydroxyl group and a freely ionized H on either end such as a hydrogen from the NH sub 2 sub in nylon or proteins . Normally, two or more different monomers are used ... acid and an alcohol monomer . Nylon is another common condensation polymer. It can be manufactured ... molecule Image Condensation polymerization diacid diamine.svg thumb left 400px General chemical structure of one type of condensation polymer clear The carboxylic acids and amines link to form peptide bond s, also known as amide groups. Protein s are condensation polymers made from amino acid monomers. Carbohydrates are also condensation polymers made from sugar monomers such as glucose and galactose. Condensation polymerization is occasionally used to form simple hydrocarbons. This method, however .... Condensation polymers, unlike addition polymer s, may be biodegradable. The peptide or ester bonds ... chain into smaller pieces. The most commonly known condensation polymers are proteins, fabrics such as nylon ... more details
Self condensation is an organic reaction in which a chemical compound containing a carbonyl group acts both as the electrophile and the nucleophile in an aldol condensation . It is also called a symmetrical aldol condensation as opposed to a mixed aldol condensation in which the electrophile and nucleophile are different species. For example, two molecules of acetone condense to a single compound mesityl oxide in the presence of an ion exchange resin ref Ketone Condensations Using Sulfonic Acid Ion Exchange Resin N. Lorette J. Org. Chem. 1957 22 3 346 347. ref 2 CH sub 3 sub COCH sub 3 sub &rarr CH sub 3 sub sub 2 sub C CH CO CH sub 3 sub H sub 2 sub O For synthetic uses, this is generally an undesirable, but spontaneous and favored side reaction of mixed aldol condensation, and special precautions are needed to prevent it. References references Category Condensation reactions ja ... more details
Acyloin condensation is a Redox reductive coupling of two carboxylic ester s using metallic sodium to yield an hydroxyketone, also known as an acyloin. ref cite journal title Action du sodium sur les thers des acides monobasiques fonction simple de la s rie grasse author Bouveault, L., and R. Loquin journal Comptes rendus de l Acad mie des sciences Comptes. Rendus. volume 140 issue pages 1593 1595 year 1905 url http gallica.bnf.fr ark 12148 bpt6k30949 f1689.table doi ref ref cite journal title The Acyloin Condensation as a Cyclization Method author Finley, K. T. journal Chemical Reviews volume 64 issue 5 pages 573 589 year 1964 doi 10.1021 cr60231a004 ref ref Bloomfield, J. J. Owsley, D. C. Nelke, J. M. Organic Reactions Org. React. 1976 , 23 . ref Image Acyloin Condensation.png center 350px The acyloin condensation The reaction is most successful when R is Aliphatic compound aliphatic and inert . To achieve the condensation, the reaction is performed in an aprotic solvent s with a high boiling point , such as benzene and toluene . Usage of protic solvents results in the Bouveault Blanc reduction of the separate esters rather than condensation. Depending on ring size and steric conformational properties, but independent from high dilution, the acyloin condensation of diesters favours intramolecular cyclisation over intermolecular polymerisation . why? mechanism Image Intramolecular acyloin condensation.png center 273px The acyloin condensation Mechanism The mechanism consists ... Acyloin condensation http www.organic chemistry.org namedreactions acyloin condensation.shtm ref Image Acyloin condensation mecanism2.png center 550px The acyloin condensation Variations R hlmann ... deactivation of the sodium sand References Reflist See also Benzoin condensation Bouveault Blanc reduction Claisen condensation Dieckmann condensation Category Condensation reactions Category Organic redox reactions cs Acyloinov kondenzace de Acyloin Kondensation es Condensaci n acilo nica fr Condensation ... more details
In mathematics, a condensation point p of a subset S of a topological space , is any point p , such that every open neighborhood of p contains uncountably many points of S . Thus, condensation point is synonymous with math aleph 1 math accumulation point . References Walter Rudin , Principles of Mathematical Analysis , 3rd Edition, Chapter 2, exercise 27 John C. Oxtoby , Measure and Category , 2nd Edition 1980 , p. 23 See also Limit point Countable set Category Mathematical objects topology stub ru ... more details
Image claisen condensation overall.png 400px right The overall reaction of the classic Claisen condensation. The Claisen condensation reaction condensation not to be confused with the Claisen rearrangement is a carbon carbon bond forming organic reaction reaction that occurs between two ester s or one ester and another carbonyl compound in the presence of a strong base , resulting in a keto ester or a di ketone ref cite book first Francis A. last Carey year 2006 title Organic Chemistry edition Sixth publisher McGraw Hill location New York, NY isbn 0 07 111562 5 ref . It is named after Rainer Ludwig Claisen , who first published his work on the reaction in 1881 ref Claisen, L., and A. Claparede ... of enolizable and nonenolizable carbonyl compounds that form a few different Claisen condensation ... condensations, since virtually all ester will be converted to ester enolate and condensation will not occur ... used. Types Image claisen ethyl acetate.png 350px br The classic Claisen condensation, where only ... condensation, where an enolizable ester or ketone and a nonenolizable ester are used. Image dieckmann example.png 500px br The Dieckmann condensation , where a molecule with two ester groups reacts intramolecular ... not be ring strain strained , usually a 5 or 6 membered chain or ring. Mechanism Image Claisen condensation ... reaction. That is, Claisen condensation does not work with Substrate chemistry substrates ... in the last step. Stobbe condensation The Stobbe condensation ref Hans Stobbe, Ann., 308, 89 1899 . ref ... Stobbe condensation A reaction mechanism which explains the formation of both an ester ... Stobbe condensation mechanism See also Aldol condensation fatty acid metabolism Synthesis fatty acid synthesis Polyketide synthase Dieckmann condensation References Reflist External links http www.organic chemistry.org namedreactions claisen condensation.shtm Organic Chemistry Portal Claisen Condensation DEFAULTSORT Claisen Condensation Category Condensation reactions Category Name reactions ... more details
The Pechmann condensation is a synthesis of coumarin s, starting from a phenol and a carboxylic acid or ester containing a carbonyl group ref J. A. Joule, K. Mills Heterocyclic Chemistry , 4th edition, Blackwell Science, Oxford, UK, 2000. ref . The condensation is performed under acidic conditions. The mechanism involves an esterification transesterification followed by attack of the activated carbonyl ortho to the oxygen to generate the new ring. The final step is a dehydration, as seen following an aldol condensation . It was discovered by the Germany German chemist Hans von Pechmann ref cite journal author H. v. Pechmann title Neue Bildungsweise der Cumarine. Synthese des Daphnetins journal Berichte der deutschen chemischen Gesellschaft year 1884 volume 17 issue 1 pages 929 936 doi 10.1002 cber.188401701248 ref . With simple phenols, the conditions are harsh, although yields may still be good ref Eugene H. Woodruff , Organic Syntheses, Coll. Vol. 3 , p.581. http www.orgsyn.org orgsyn prep.asp?prep cv3p0581 Available online . ref . Image Pechmann 4methyllcoumarin.png center 600px The Pechmann condensation as applied to 4 methylcoumarin With highly activated phenols such as resorcinol , the reaction can be performed under much milder conditions. This provides a useful route to umbelliferone derivatives Image Pechmann 4methylumbelliferone.png center 450px The Pechmann condensation as applied to 7 hydroxy 4 methylcoumarin For coumarins unsubstituted at the 4 position, the method requires the use of formylacetic acid or ester. These are unstable and not commercially available ..., the formylacetic acid performs the Pechmann condensation. In the example shown, umbelliferone ... condensation as applied to umbelliferone Simonis chromone cyclization In a variation the reaction of phenols ... in it is then activated for electrophilic attack of the arene. See also Aldol condensation Perkin reaction References Reflist DEFAULTSORT Pechmann Condensation Category Condensation reactions Category ... more details
The Dieckmann condensation is the intramolecular chemical reaction of ester diester s with base to give ketoesters. ref Dieckmann, W. Chemische Berichte Ber. 1894, 27 , 102 & 965 ref ref Dieckmann, W. Chemische Berichte Ber. 1900, 33 , 595 & 2670 ref ref Dieckmann, W. Ann. 1901, 317 , 51 & 93 ref ref Schaefer, J. P. Bloomfield, J. J. Org. React. 1967, 15 , 1 203. Review ref ref Davis, B. R. Garrett, P. J. Comp. Org. Syn. 1991, 2 , 806 829. Review ref It is named after the German chemist Walter Dieckmann 1869 1925 . The equivalent intermolecular reaction is the Claisen condensation . Image DieckmannCondensation.png center 350px The Dieckmann condensation Reaction Mechanism The acidic hydrogen between the two carbonyl groups is deprotonated in step four. Protonation with a Br nsted Lowry acid H sub 3 sub O sup sup for example re forms the keto ester. ref Janice Gorzynski Smith. Organic Chemistry Second Ed. 2008. pp 932 933. ref This deprotonation step is the driving force for this reaction. Image DieckmannCondensationMechanism.png center 635px Dieckmann Condensation reaction mechanism for the example given. Owing to the steric stability of five and six membered ring structures, these will preferentially be formed. 1,4 and 1,6 diesters will form five membered cyclic &beta keto esters, while 1,5 and 1,7 diesters will form six membered &beta keto esters. ref Organic Chemistry.org. Dieckmann Condensation. http www.organic chemistry.org namedreactions dieckmann condensation.shtm ref See also Claisen condensation Gabriel Colman rearrangement References Reflist Category Intramolecular condensation reactions ca Condensaci de Dieckmann de Dieckmann Kondensation es Condensaci n de Dieckmann it Condensazione di Dieckmann nl Dieckmann condensatie ja pt Condensa o de Dieckmann zh ... more details
The condensation algorithm Con ditional Dens ity Propag ation is a computer vision algorithm. The principal application is to detect and video tracking track the contour of objects moving in a cluttered environment. Object tracking is one of the more basic and difficult aspects of computer vision and is generally a prerequisite to object recognition. Being able to identify which pixels in an image make up the contour of an object is a non trivial problem. Condensation is a probabilistic algorithm that attempts to solve this problem. The algorithm itself is described in detail by Isard and Andrew Blake scientist Blake in a publication in the International Journal of Computer Vision in 1998. One of the most interesting facets of the algorithm is that it does not compute on every pixel of the image. Rather, pixels to process are chosen at random, and only a subset of the pixels end up being processed. Multiple hypotheses about what is moving where are supported naturally by the probabilistic nature of the approach. The evaluation functions come largely from previous work in the area and include many standard statistical approaches. The original part of this work is the application of particle filter estimation techniques. See also Particle filter Condensation is the application of Sampling Importance Resampling SIR estimation to contour tracking External links http www.robots.ox.ac.uk misard condensation.html Condensation homepage http www.springerlink.com link.asp?id xl887466h454318k Condensation conditional density propagation for visual tracking , by Michael Isard and Andrew Blake International Journal of Computer Vision 29 1 5 28, August 1998 Signal processing stub Category Computer vision no Condensation algoritmen ... more details
. Tachyon condensation drives the physical system to a stable state where no physical tachyons exist ... , Perseus books publishing. ref Tachyon condensation in string theory In the late 1990s, the Indian ... Sen title Tachyon condensation on the brane antibrane system journal JHEP volume 08 year 1998 pages ... condensation is more subtle, though the first steps towards our understanding of their fate have ..., though recent progress has revealed interesting new developments. See also Bose Einstein condensation a condensation process that was experimentally observed 70 years after it was theoretically proposed ... 2&index1 3877000 Tachyon condensation on arxiv.org DEFAULTSORT Tachyon Condensation Category String ... more details
The Knoevenagel condensation reaction is an organic reaction named after Emil Knoevenagel . It is a modification of the Aldol condensation ref Jones, G. Organic Reactions Org. React. 1967 , 15 . ref ref cite journal author Emil Knoevenagel title Condensation von Malons ure mit Aromatiachen Aldehyden durch Ammoniak und Amine journal Berichte der deutschen chemischen Gesellschaft year 1898 volume 31 issue pages 2596 2619 url http gallica.bnf.fr ark 12148 bpt6k90751n f268.chemindefer doi 10.1002 cber.18980310308 ref . A Knoevenagel condensation is a nucleophilic addition of an active hydrogen compound to a carbonyl group followed by a dehydration reaction in which a molecule of water is eliminated hence condensation . The product is often an alpha, beta conjugated system conjugated enone . Image KnoevenagelGeneral.png center 400px General Knoevenagel layout In this reaction the carbonyl group is an aldehyde or a ketone . The catalyst is usually a weakly base chemistry basic amine . The active hydrogen component has the form ref JerryMarch ref Z CH sub 2 sub Z or Z CHR Z for instance diethyl malonate , Meldrum s acid , ethyl acetoacetate or malonic acid . Z CHR sub 1 sub R sub 2 sub for instance nitromethane . where Z is an polar effect electron withdrawing functional group . Z must be powerful enough to facilitate hydrogen abstraction to the enolate ion even with a mild base. Using a strong base in this reaction would induce self condensation of the aldehyde or ketone. The Hantzsch ... condensation. Acrolein and malonic acid react in pyridine to give trans 2,4 pentadienoic ... A Knoevenagel condensation is demonstrated in the reaction of 2 methoxybenzaldehyde 1 with the barbituric ... A knoevenagel condensation The Knoevenagel condensation is a key step in the commercial production ... be obtained. A multicomponent reaction featuring a Knoevenagel condensation is demonstrated in this MORE ... Reflist Category Condensation reactions Category Name reactions de Knoevenagel Reaktion es Condensaci n ... more details
An aldol condensation is an organic reaction in which an enol or an enolate ion reacts with a carbonyl ... to give a conjugated enone . Image AldolcondensationGeneral.png 600px center Aldol condensation ... carbon bond s. The Robinson annulation reaction sequence features an aldol condensation the Wieland ... center 600px The Aldol reaction The name aldol condensation is also commonly used, especially in biochemistry ... is not formally a condensation reaction because it does not involve the loss of a small molecule. The reactions between a ketone and an aldehyde crossed aldol condensation or between two aldehydes also go by the name Claisen Schmidt condensation . These reactions are named after two of its pioneering ... Enolate mechanism Image Enol aldol mechanism.png 450px Enol Mechanism Condensation types It is important to distinguish the aldol condensation from other addition reaction s to carbonyl compounds. When ... a Knoevenagel condensation . In a Perkin reaction the aldehyde is aromatic and the enolate generated from an anhydride . A Claisen condensation involves two ester compounds. A Dieckmann condensation ... to the aldol condensation. In the Guerbet reaction , an aldehyde, formed in situ from an alcohol, self condenses to the dimerized alcohol. In the Japp Maitland condensation water is removed not by an elimination ... via hydroformylation to butyraldehyde , aldol condensation to 2 ethylhexenal and finally hydrogenation ... 2 methylacetoacetate and campholenic aldehyde react in an Aldol condensation. ref E 6 2,2,3 Trimethyl ... Aldol condensation of Ethyl 2 methylacetoacetate and campholenic aldehyde Ethyl glyoxylate 2 and glutaconate ... 500px Isoprenetricarboxylic acid Occasionally an aldol condensation is buried in a multistep reaction ... 1 is converted into a cycloalkene 7 with a ruthenium catalyst and the actual condensation takes ... 3 followed by aldol condensation to 5 at which stage a molecule of carbon monoxide is lost to 6 . The final ... below ref Simple and Effective Protocol for Claisen Schmidt Condensation of Hindered Cyclic ... more details
wave. Analysts of nuclear bomb tests later used the more general term condensation cloud ... of the Wilson clouds. During nuclear test s, condensation rings around or above the fireball are commonly ... the droplets. The same kind of condensation cloud is sometimes seen above the wings of low altitude ... by Bernoulli s Law . This reduction in air pressure causes a cooling, just as above, and the condensation ... more details
Orphan date February 2009 The building of Condensation traps or moisture traps as they are more commonly known amongst Survivalists is a Survival skills survival skill to collect drinking water . History Condensation traps have been in use since the pre Incan peoples inhabited the Andes . Today a method for gathering water in moisture traps is still taught within the Military of Argentina Argentinian Army for use by specialist units expected to conduct extended patrols of more than a weeks duration in the arid border areas of the Andes . Methods Several methods of trapping condensation exist First method This method was first used by the peoples of the Andes . A pit is dug into the earth, at the bottom of which is placed the receptacle that will be used to catch the condensed water. Small branches are placed with one of their ends end inside the receptacle and their other ends up over the edge of the pit, forming a funnel to direct the condensed water into the receptacle. A lid is then built over this funnel, using more small branches, leaves, grasses, etc. The completed trap is left overnight, and moisture can be collected from the receptacle in the morning. This method relies on the formation of dew or frost on the receptacle, funnel, and lid. Forming dew collects on and runs down the outside of the funnel and into the receptacle. This water would typically evaporate with the morning sun and thus vanish, but the lid traps the evaporating water and raises the humidity within the trap, reducing the amount of water that is lost. The shade produced by the lid also reduces the temperature ... of effort. Condensation Trap Efficiency condensation traps are not in themselves a sustainable .... Condensation Traps in Popular Culture Condensation traps are common in survivalist fiction. The 1972 ... sheet condensation trap. In the novel Life of Pi , a number of traps are towed behind a life raft. Condensation Traps and Human Urine It is well known among survivalists that using a condensation ... more details
exhibiting capillary condensation. Capillary Condensation is the process by which multilayer ... aspect of capillary condensation is that vapor condensation occurs below the saturation vapor .... Once condensation has occurred, a meniscus immediately forms at the liquid vapor interface ... confined space with respect to its surroundings. Capillary condensation is an important factor in both ... of capillary condensation to determine pore size distribution and surface area though adsorption ... 505. ref of materials are also highly dependent on bridging effects resulting from capillary condensation. In contrast to the advantages of capillary condensation, it can also cause many problems in materials ... of capillary condensation due to the presence of a curved meniscus ref name hunter . math ln frac ... reasoning for the fact that condensation of a given species occurs below the saturation vapor ... . Therefore, the variables that govern capillary condensation most are the equilibrium vapor pressure ... 1 sub P sub sat sub , capillary condensation occurs and liquid vapor Vapor liquid equilibrium equilibrium ... pressure is increased condensation continues in order to satisfy the Kelvin equation System D P sub ... pressure in a given system, more condensation will occur. In a porous medium , capillary condensation ... vapor condensation. See the discussion on contact angle below. Figure 2 above demonstrates this dependence ... and thus vapor condensation occurs smoothly over a range of vapor pressures . In a parallel situation, where the capillary radius is constant throughout its height, vapor condensation would ... of capillary condensation, the hemispherical meniscus situation that resulting from a perfectly cylindrical ... in capillary condensation. The Young Equation explains that the surface tension between the liquid and vapor ... equation complicated very quickly. Adsorption isotherm studies utilizing capillary condensation ... dependent processes. For example, if a capillary s radius increases sharply, then capillary condensation ... more details
Refimprove article date June 2010 Wealth condensation is a theoretical process by which, in certain conditions, newly created wealth tends to become concentrated in the possession of already wealthy individuals or entities, a form of preferential attachment . According to this theory, those who already ... satisfied in developed nations in 2005. In their wealth condensation model J. P. Bouchaud & M. Mezard ... model economies showing that wealth condensation can occur whether or not total wealth is growing if it is not, this implies ... condensation have been proposed Either A correlation between being rich and being given high ... below one, these are automatic causes of wealth condensation due to variable incomes. The following ... wage s. Positive net real rate of return to capital This condition would bring wealth condensation ... positive net return to capital that widespread wealth condensation is most likely. Wealth condensation ..., wealth condensation will also occur if the largest owners on average receive a higher return than smaller owners this would constitute wealth condensation within the capitalist class rather than ... inflation is sometimes said to be a Wealth Tax , which prevents wealth condensation. Furthermore ... condensation. Some of the causes may include Cost of living is typically the same for everyone ... can hold government office, it should be expected that wealth condensation will follow. Critics ... were being scrapped in favor of regressive tax systems, driving wealth condensation by allowing the wealthy ... guru Robert Kiyosaki both believe that wealth condensation is common throughout democratic countries .... Support Wealth condensation is generally defended by proponents of capitalism. Many of them argue that the argument for wealth condensation is based on the principal assumption that wealth is neither ... that wealth condensation theory applies less strongly to democratic countries. They argue that the United ... at Jagiellonian University , 2002 Wealth condensation in Pareto macroeconomies model appears in Physical ... more details
The benzoin condensation is a reaction often called a condensation reaction , for historical reasons between two aromatic aldehyde s, particularly benzaldehyde . The reaction is catalysis catalyzed by a nucleophile such as the cyanide anion or an persistent carbene N heterocyclic carbene . The reaction product is an aromatic acyloin with benzoin as the parent compound. ref OrgSynth title Benzoin author Roger Adams and C. S. Marvel collvol 1 collvolpages 94 year 1941 prep cv1p0094 ref An early version of the reaction was developed in 1832 by Justus von Liebig and Friederich Woehler during their research on almond bitter almond oil . ref cite journal title Untersuchungen ber das Radikal der Benzoes ure author W hler, Liebig journal Annalen der Pharmacie volume 3 issue 3 pages 249 282 year 1832 url doi 10.1002 jlac.18320030302 last2 Liebig ref The catalytic version of the reaction was developed by Nikolay Zinin in the late 1830s, ref cite journal title Beitr ge zur Kenntniss einiger Verbindungen aus der Benzoylreihe author N. Zinin journal Annalen der Pharmacie volume 31 issue 3 pages 329 332 year 1839 url doi 10.1002 jlac.18390310312 ref ref cite journal title Ueber einige Zersetzungsprodukte des Bittermandel ls author N. Zinin journal Annalen der Pharmacie volume 34 issue 2 pages 186 192 year 1840 url doi 10.1002 jlac.18400340205 ref and the reaction mechanism for this organic reaction was proposed in 1903 by Arthur Lapworth A. J. Lapworth . ref CXXII. Reactions involving the addition ... condensation reaction mechanism. Proton transfers occur at i and ii . In the first step in this reaction ... condensation is in effect a Dimerization chemistry dimerization and not a condensation because a small ... to facilitate an enantioselective intramolecular benzoin condensation Scheme 2 . ref cite journal ... thumb center 500px Scheme 2. An intramolecular benzoin condensation This finding was confirmed .... A second intramolecular benzoin condensation References references Category Condensation reactions ... more details
DNA condensation refers to the process of compacting DNA molecules in vitro or in vivo . ref name Teif cite journal author Teif V.B. and Bohinc K. year 2010 title Condensed DNA condensing the concepts journal Progress in Biophysics and Molecular Biology doi 10.1016 j.pbiomolbio.2010.07.002 ref Mechanistic details of DNA packing are essential for its functioning in the process of gene regulation in living systems. Condensed DNA often has surprising properties, which one would not predict from classical concepts of dilute solutions. Therefore DNA condensation in vitro serves as a Scientific model ... journal author Bloomfield V.A. year 1996 pages 334 title DNA condensation volume 6 journal Current Opinion in Structural Biology doi 10.1016 S0959 440X 96 80052 2 ref In addition, DNA condensation has ... solution conditions with the help of ions and other molecules. Usually, DNA condensation ... 269 title DNA condensation by multivalent cations volume 44 journal Biopolymers doi 10.1002 SICI ... and is also close to the definition of DNA condensation in bacteria as adoption of relatively concentrated ... and the mandatory condensation of DNA in bacteria volume 390 journal FEBS Letters doi 10.1016 0014 5793 ... is just the first of many levels of DNA packing. ref name Teif DNA condensation in viruses In virus ... ordered and fluid. ref name Teif DNA condensation in bacteria Bacterial DNA is packed with the help .... ref name Teif DNA condensation in eukaryotes Eukaryotic DNA with a typical length of dozens ... of the two daughter cells. ref name Teif DNA condensation in vitro DNA condensation can be induced ... of DNA condensationCondensation of long double helical DNAs is a sharp phase transition , which ... correlations between counterions in the solution. ref DNA condensation and gene regulation Most .... 2002. Compaction and condensation of DNA. In Pharmaceutical perspectives of nucleic acid based ... Biology state expanded DEFAULTSORT Dna Condensation Category DNA Category Nucleic acids Category ... more details
In set theory , a branch of mathematics, the condensation lemma is a result about sets in the constructible universe . It states that if math L alpha math is a level of the constructible hierarchy, X is an elementary submodel of the model math L alpha, in math then math X, in math is isomorphic to some math L beta, in math , math beta leq alpha math . The lemma was formulated and proved by Kurt G del in his proof that the axiom of constructibility implies Continuum hypothesis The generalized continuum hypothesis GCH . References cite book last Devlin first Keith authorlink Keith Devlin year 1984 title Constructibility publisher Springer id ISBN 3 540 13258 9 Category Set theory Category Lemmas settheory stub ... more details
Unreferenced date October 2006 Orphan date November 2009 In particle physics , gaugino condensation is the nonzero vacuum expectation value in some models of a bilinear expression constructed in theories with supersymmetry from the superpartner of a gauge boson called the gaugino . The gaugino and the bosonic gauge field and the D term are all components of a supersymmetric vector superfield in the Wess Zumino gauge . math langle lambda a alpha lambda b beta rangle sim delta ab epsilon alpha beta Lambda 3 math where math lambda math represents the gaugino field a spinor and math Lambda math is an energy scale, a and b represent Lie algebra indices and and represent van der Waerden notation van der Waerden indices. The mechanism is somewhat analogous to chiral symmetry breaking and is an example of a fermionic condensate . In the superfield notation, math W alpha equiv overline D 2 D alpha V math is the gauge field strength and is a chiral superfield . math langle W a alpha W b beta rangle langle lambda a alpha lambda b beta rangle sim delta ab epsilon alpha beta Lambda 3 math math W alpha W beta math is also a chiral superfield and we see that what acquires a nonzero VEV is not the F term of this chiral superfield. Because of this, gaugino condensation in and of itself does not lead to supersymmetry breaking. If we also have supersymmetry breaking, it is caused by something other than the gaugino condensate. However, a gaugino condensate definitely breaks R symmetry U 1 sub R sub symmetry as math lambda a alpha lambda b beta math has an R charge of 2. DEFAULTSORT Gaugino Condensation Category Supersymmetry Category Gauge theories Particle stub ... more details
The counterion condensation phenomenon is commonly described by Manning s theory Manning 1969 , which assumes that counterion counterions can condense onto the polyions until the charged density between neighboring monomer charges along the polyion chain is reduced below a certain critical value. In the model the real polyion chain is replaced by an idealized line charge, where the polyion is represented by a uniformly charged thread of zero radius, infinite length and finite charge density, and the condensed counterion layer is assumed to be in physical equilibrium with the ionic atmosphere surrounding the polyion. The uncondensed mobile ions in the ionic atmosphere are treated within the Debye H ckel equation Debye H ckel DH approximation. The phenomenon of counterion condensation now takes place when the dimensionless Coulomb coupling strength math Gamma lambda B l charge 1 math , where math lambda B math represents the Bjerrum length and math l charge math the distance between neighboring charged monomer monomers . In this case the The Coulomb potential Coulomb interactions dominate over the thermal interactions and counterion condensation is favored. For many standard polyelelctrolyte polyelectrolytes , this phenomenon is relevant, since the distance between neighboring monomer charges typically ranges between 2 and 3 and math lambda B approx math 7 in water. In the case of the chondroitin sulfate CS systems, which is a major biopolyelectrolyte controlling the frictional compressive properties of articular cartilage, the Coulomb coupling strength math Gamma approx math 1.4, which implies that according to Manning s theory counterion condensation should take place. However, since Manning s theory does not take into account the molecular details of real polyion chains ... 2009 have recently demonstrated that the phenomenon of counterion condensation disappears in the limit ... first G.S. title Limiting Laws and Counterion Condensation in Polyelectrolyte Solutions I. Colligative ... more details
The Ullmann condensation or Ullmann ether synthesis is a variation of the Ullmann reaction , in which a phenol is coupled to an aryl halide to create a diaryl ether in the presence of a copper compound, named after Fritz Ullmann . ref cite journal title Ueber die Phenylirung von Phenolen author Fritz Ullmann , Paul Sponagel journal Berichte der deutschen chemischen Gesellschaft volume 38 issue 2 pages 2211 2212 year 1905 url doi 10.1002 cber.190503802176 ref The corresponding aniline or aryl amide reaction is sometimes called Goldberg reaction , named after Irma Goldberg . ref cite journal title Ueber Phenylirungen bei Gegenwart von Kupfer als Katalysator author Iram Goldberg journal Berichte der deutschen chemischen Gesellschaft volume 39 issue 2 pages 1691 1692 year 1906 url doi 10.1002 cber.19060390298 ref An example is the synthesis of p nitrophenyl phenyl ether ref Ray Q. Brewster and Theodore Groening, Ether, p nitrophenyl phenyl , Organic Syntheses , Coll. Vol. 2, p.445 http www.orgsyn.org orgsyn prep.asp?prep cv2p0445 Online article ref Image UllmannCondensation.svg center An active copper powder that is required for this reaction can be prepared by the Redox reduction of copper sulfate by zinc metal in hot water causing the Precipitation chemistry precipitation of elementary copper. The reaction often requires high boiling polar solvents such as N methylpyrrolidone , nitrobenzene or dimethylformamide and high temperatures often in excess of 210 C with stochiometric amounts of copper. The aryl halide is activated by electron withdrawing group s or carries a carboxylic acid group in the aromatic ortho position ref Minireview Catalytic CC, CN, and CO Ullmann Type Coupling Reactions Florian Monnier, Marc Taillefer Angewandte Chemie International Edition Volume 48 Issue ... Accelerated Catalysis of the Ullmann Condensation Application to Hole Conducting Triarylamines author ... DEFAULTSORT Ullmann Condensation Category Carbon heteroatom bond forming reactions Category Condensation ... more details
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